1. Field of the Invention
The present invention relates to a method for manufacturing a cake composition which is useful for the treatment of the flush water of toilets. More particularly, the invention relates to a method for manufacturing a cake composition with a long lasting iodophor-containing toilet tank dispenser which provides improved cleaning, a sanitizing action and is responsive to the flushing of the toilet.
2. Background Art of the Invention
It is desirable that chemicals be automatically dispensed into toilet flush water each time a toilet is flushed in order to produce desirable bowl aesthetics, cleaning, disinfection, deodorization, aerosol reduction, or other desirable effects. The background art discloses numerous devices which are designed for one or more of these purposes.
Particularly desirable devices are those comprising a solid cake composition. A measured amount of water, in this type of device, enters the device during one flush cycle and remains in contact with the cake between flushes, thereby forming a concentrated solution of the composition. The concentrated solution of the composition is then dispensed into the flush water during the next flush. The advantages of such devices are that the chemical composition can be packaged and shipped in more concentrated form than aqueous solutions of the chemicals. Also, there is no problem with liquid spillage, that can result from breakage of the dispensers during shipment or handling.
U.S. Pat. No. 4,780,236 to Bunczk, et al., issued Oct. 25, 1988, herein incorporated by reference, discloses a lavatory cleansing block containing polyethylene glycol distearate, guar gum, and sodium chloride. This patent, particularly in columns 3 through 5, identifies a variety of compositions and their concentrations for use in manufacturing a lavatory cleansing block or "toilet cake". This patent does not disclose a method for manufacturing such a block with a dye and iodophor composition that release from the block during substantially the same period of time.
U.S. Pat. Nos. 4,308,625 to Kitko, issued Jan. 5, 1982, and 4,043,931 to Jeffrey, et al., issued Aug. 23, 1977, are examples of surfactant cake compositions. These patents disclose lavatory cleansing tablets which are formed with two or more nonionic surfactants and which include the use of polyalkoxylated alcohols.
U.S. Pat. No. 4,477,363 to Wong, et al., issued Oct. 16, 1984, discloses a solid cake comprising free fatty alcohol and a buffered alkali earth metal alkyl sulfate surfactant.
U.S. Pat. Nos. 4,310,434 Choy, et al., issued Jan. 12, 1982, and 4,278,571 to Choy, issued July 14, 1981, are entitled "Surfactant Cake Compositions" and are both incorporated herein by reference. These two patents disclose surfactant cake compositions containing dyes and perfumes which can be utilized in the present invention. The surfactants provide cleaning and sudsing activity in the toilet bowl and also serve to dispense other components of the compositions such as dyes, perfumes, and organic resins into the toilet water.
Water-soluble inert salts such as alkali metal chlorides and sulfates are used in such compositions to act as a "filler" so that the composition can be formed into cakes of desirable size without using excessive amounts of active ingredients. The predominant ingredients of the cake compositions are usually the surfactant, perfume, and the filler salt.
Automatically dispensed toilet bowl cleaning and/or sanitizing products, which contain dyes to provide a visual signal to the user that the product is being dispensed, are well known. Such products are sold in the United States under the brand names VANISH AUTOMATIC (Drackett Products), TY-D-BOL AUTOMATIC (Kiwi Brands, Inc.) and SANIFLUSH AUTOMATIC (Boyle-Midway). None of these products contain an iodophor sanitizing agent and all of them provide a color to the bowl water which persists between flushings. U.S. Pat. No. 3,504,384 to Radley et al., issued Apr. 7, 1970, discloses a dual compartment dispenser for automatically dispensing a hypochlorite solution and a surfactant/dye solution to the toilet bowl during flushing. The dye which is taught in the patent is Disulfide Blue VN150. This dye is resistant to oxidation to a colorless state by the hypochlorite. Thus, the dye provides a persistent color to the toilet bowl water, even in the presence of the hypochlorite.
The Environmental Protection Agency has established efficacy data requirements for in-tank sanitizer product claims for effectiveness. It is necessary under these requirements that the user be able to determine the duration of the product's effectiveness. That is, the color indicator of the product must show that the sanitizing ingredient is still present in a sanitizing amount or guarantee a specific life or number of flushes. Consequently, it is essential that the sanitizing agent have the same life in the sanitizing product as the color indicator.
The use of chlorine or hypochlorite ion as the sanitizing agent has the disadvantage that most dyes are oxidized to a colorless state by these compounds and there is no visual indication that the sanitizing agent is active and working in the toilet bowl.
The use of iodine-containing formulations have been previously considered as sanitizing agents for toilets because of their greater sanitizing capabilities than the sanitizing capabilities of chlorine-containing agents. However, the iodine-containing agents have not been previously employed in cake toilet compositions because they yield an unacceptable color in the toilet bowl. Also, prior to the present invention, there has not been a means for providing a controlled release of iodine so that the iodine and the dye will last for the life of the cleansing block. The most effective means to date for such products provides the iodine in a germicidal complex of iodine with a copolymer. These iodine complexes are commonly identified as an iodophor.
It is an object of the present invention to provide a method for manufacturing a solid cake, containing iodophors, which is suitable for use for automatically dispensing cleaning agents into a toilet.
It is another object of the present invention to provide a method for manufacturing a filler for a lavatory block which has a uniform distribution of iodophor throughout an adsorbent-containing dry filler composition.
It is still a further object of the present invention to provide a method for manufacturing a lavatory block having a long and uniform block life that provides a controlled release of iodophor.
It is a yet still further object of the present invention to provide a method for manufacturing an iodophor-containing lavatory block which releases a dye and an iodophor for substantially the same period of time.
Other objects, advantages, and novel features of the present invention will be apparent to those skilled in the art from the following description and appended claims.